This is a mini piano board with only 4 customizable buttons allowing you to play any frequency and tone you want. It is a simple yet fun toy to build especially for kids!

Here's also a recording of my happy birthday-twinkle twinkle Arduino remix!

Step 1: Materials and Tools

Arduino
4x Push button switches
4x 10kΩ resisitor
6x jumper wires
Breadboard wires
Breadboard

Step 2: Connecting to Ground

Connect one of the pins of each of the switches to ground.
Connect one of the buzzer pins to ground.

It doesn't matter which one you connect since the remaining pin will be the signal pin.

Step 3: Connecting the Resistors

Connect each of the 10kΩ resistor between power (red power rail) to one of the pins of each switch, this is also known as the signal pin.
Connect this power rail to 3.3V.

Step 4: Connecting the Signal

Connect the signal pin of each switch to pins 2-5 on the Arduino.

Step 5: Coding and Uploading

Upload the following code to your Arduino, once you have selected the appropriate board and port under tools.

const int yellow = 2;
const int green = 3;
const int blue = 4;
const int red = 5;
const int buzz = 6;

int notes[] = {262,294,330,349};

void setup() {
  pinMode (yellow, INPUT);
  pinMode (green, INPUT);
  pinMode (blue, INPUT);
  pinMode (red, INPUT);

  pinMode (buzz, OUTPUT);
  tone (buzz, 2000);
  Serial.begin(9600);
}

void loop() {
  if (digitalRead(yellow) == LOW)
    {tone(buzz, notes[0], 50);
    delay (50);
    noTone(buzz);
    Serial.println(digitalRead(yellow));}

  else if (digitalRead(green) == LOW)
    {tone (buzz, notes[1], 50);
    delay (50);
    noTone(buzz);}
  else if (digitalRead(blue) == LOW)
    {tone (buzz, notes[2], 50);
    delay (50);
    noTone(buzz);}
  else if (digitalRead(red) == LOW)
   {tone (buzz, notes[3],50);
    delay (50);
    noTone(buzz);}
  else 
    noTone (buzz);
}